Toa HFD-220-8/16 Specifications

TOA PROFESSIONAL SOUND SYSTEM

COMPRESSION DRIVER

HFD-220-8/16

DESCRIPTION

The TOA HFD-220-8/16 compression driver, in 8-ohm and

16-ohm versions, is designed for use in high-level
applications where sound systems of the highest quality are
required. With a throat diameter of 2 in. (49mm), the TOA
HFD-220-8/16 is intended for use with the TOA LE Series
constant directivity horns, and it will provide highly efficient
sound reproduction and a smooth frequency response from
800Hz to 15kHz. The voice coil of the TOA HFD-220-8/16
compression driver consists of a 1.76 in. (44.6mm) edge­wound, copper-clad aluminum ribbon coupled to a 50­micron hard duralumin diaphragm. The diaphragm voice
coil assembly can be replaced in the field without having to
disassemble the entire driver. The diaphragm voice coil
employs self-aligning dowels to center it perfectly in the
voice coil gap. The gap has a flux density of 19,000 gauss,
generated by a 2.4 Ibs. (1.1 kg) ferrite magnet. A machined
phasing plug with two acoustic slots serves as the pole
piece, providing the proper phase relationship between the
sound emanating from the center and that coming from the
edge of the diaphragm/voice coil assembly.

FEATURES

1. Smooth frequency response from 800Hz to 15kHz.

2. Highly efficient sound pressure level of 110dB/W/m
with LE-940 horn.

3. High power capacity: 30 watts continuous pink noise

(800Hz to 20kHz, test duration: 24 hours).

4. Throat diameter of 2 in. (49mm).

5. Edge-wound, copper-clad aluminum ribbon voice coil.

6. 50-micron duralumin diaphragm.

7. Diaphragm voice coil can be easily replaced in the

field.

SPECIFICATIONS

Power Handling Capacity

Continuous Pink Noise
Continuous Program

Nominal Impedance

Frequency Response

Pressure Sensitivity

800Hz to 5kHz pink noise
4-meter measurement
distance referred to
1 meter

Recommended Crossover

Frequency

Throat Diameter

Polarity

Recommended Horn

Magnet

Diaphragm

Voice Coil

Finish
Dimensions

Net Weight
Mounting Data

30 watts RMS band-limited pink noise
(800Hz to 20kHz)
90 watts

8 ohms (HFD-220-8)

16 ohms (HFD-220-16)

800Hz to 15kHz

110dB/W/m: LE-940 horn
112dB/W/m: LE-640 horn
114dB/W/m: LE-420 horn
108dB/W/m: LE-M124 horn
10SdB/W/m: LE-M94 horn
112dB/W/m: LE-M64 horn
114dB/W/m: LE-M42 horn

800Hz or higher

2" (49mm)
Positive voltage to +terminal produces

negative acoustic pressure in the throat
LE-940, LE-640, LE-420

LE-M124, LE-M94, LE-M64, LE-M42

2.4 Ibs. (1.1 kg) Ferrite
Flux density: 19,000 gauss

Heat-treated 50-micron duralumin

1.76" (44.6mm) dia., edge-wound

copper-clad aluminum ribbon
Black NEW-ALKONE paint

5.98" (152mm) dia.

7.01" (178mm) depth

10.6 Ibs. (4.8kg)

Four studs [0.24" (6mm) dia.] equally
spaced on a 4" (101.6mm) dia. circle

APPEARANCE AND DIMENSIONAL DIAGRAM

66.0" (152mm) DIA

EQUALIZATION

When using the HFD-220-8/16 driver in combination with the LE Series
constant directivity horn and the TOA “SAORI” integrated sound
processor, set the long delay type horn equalizer (IS-110DL4, IS-110DL2)
built into the digital channel divider module of the “SAORI” as shown in the
table below.

LE-640

HFD-220-8/16

LE-940

TYPE 6

TYPE 6

LE-420

TYPE 7 TYPE 8

LE-M124

LE-M94 LE-M64

TYPE 8 TYPE 8

LE-M42

TYPE 9

1. Measurement conditions:
The above electrical and acoustic data are measured in conjunction with TOA’s LE-M94 horn.

2.

Duration of power handling test is 24 hours.

*Specifications are subject to change without notice.

ARCHITECT’S AND ENGINEER’S
SPECIFICATIONS

The compression driver shall be the TOA HFD-220-8/16, in 8-ohm or 16­ohm versions, or an approved equivalent. Power handling capacity shall

be 90 watts of continuous program, 30 watts RMS band-limited pink noise

(800Hz to 20kHz), with a smooth frequency response from 800Hz to

15kHz. Pressure sensitivity with the LE-940 horn shall be 110dB/Wm,when
measured at a referred 1 -meter distance on an axis from the mouth of the
LE-940 with 1-watt input pink noise, band limited from 800Hz to 5kHz, and

the recommended crossover frequency shall be 800Hz or higher. Nominal

impedance shall be 8 ohms for the HFD-220-8 and 16 ohms for the
HFD-220-16. The unit’s throat diameter shall be 2 in. (49mm). The voice
coil shall consist of a 1.76in. (44.6mm) edge-wound, copper-clad
aluminum ribbon coupled to a 50-micron hard duralumin diaphragm.

The diaphragm voice coil assembly shall be replaceable in the field
without requiring special tools or skills. The diaphragm voice coil shall

employ self-aligning dowels to center it perfectly in the voice coil gap.

The gap shall have a flux density of 19,000 gauss generated by a 2.4 lbs.

(1.1 kg) ferrite magnet. A machined phasing plug with three acoustic slots
shall serve as the pole piece, providing the proper phase relationship
between the sound emanating from the center and that coming from the
edge of the diaphragm/voice coil assembly. The driver shall be 598 in.
(152mm) in diameter by 7.01 in. (178mm) in depth, shall weigh 10.6 lbs.
(4.8kg), and shall have a black NEW-ALKONE paint finish. Mounting shall
be effected by four 6mm studs, equally spaced on a 4in. (101.6mm)
diameter circle.

CHARACTERISTIC DIAGRAMS

• Frequency Response and Impedance

*4-meter measurement distance referred to 1 meter, 1W, sine wave.

• Harmonic Distortion

*4-meter measurement distance referred to 1 meter, 1W, sine wave.

• Frequency Response with Horn EQ

*4-meter measurement distance referred to 1 meter, 1W, sine wave, with Horn EQ Type 6
(LE-940), Type 8 (LE-M94)

Electronics, Inc., 601 Gateway Boulevard
South San Francisco, California 94080
Telephone: [phone]

FAX [phone]

© 1991 TOA Electronics, Inc.

Printed in USA 07-91